Shining a Light on BP-3 Exposure
Sunscreen Chemical Measured in U.S. Population
Sunscreens provide important protection against sunburn and
squamous cell cancer, particularly for individuals who work outdoors or
in situations where sun exposure is unavoidable. The widespread use of
the common sunscreen agent benzophenone-3 (BP-3) and its detection in
the environment suggest the need for more information about the extent
of human exposure. Results of a new study now provide the first
nationally representative data on BP-3 exposure among the U.S.
population
[
EHP 116:893–897; Calafat et al.].
BP-3 is used in personal care products to absorb and dissipate
ultraviolet (UV) radiation. It is also used as a UV stabilizer in
plastic surface coatings to prevent polymer or food photodegradation
and has been approved by the Food and Drug Administration as an
indirect food additive. Although BP-3 exposure has not been linked to
adverse health effects in humans, results of animal studies by the
National Toxicology Program have shown effects in liver, kidney, and
reproductive organs, and studies by other groups have shown
endocrine-disrupting effects.
Using data from the National Health and Nutrition Examination
Survey (NHANES) 2003–2004 conducted by the Centers for Disease Control
and Prevention, the current research team analyzed 2,517 urine samples
from three major racial/ethnic groups: non-Hispanic black, non-Hispanic
white, and Mexican American. NHANES includes household interviews,
medical histories, standardized physical examinations, and a collection
of biologic specimens that can be used to assess exposure to
environmental chemicals, as in the current study.
The scientists detected BP-3 in 96.8% of the urine samples, with a
mean concentration of 22.9 µg/L and a concentration of 1,040 µg/L in
the 95th percentile. The high level of detection likely resulted from
routine use of personal care products such as sunscreen, moisturizers,
lipstick, and hairspray.
Results of the current study suggest that females and non-Hispanic
whites were the most highly exposed of all the demographic groups
studied. Mean concentrations of BP-3 were significantly higher for
females than for males, regardless of age, probably because women and
girls use more sunscreen and other personal care products than men and
boys do. At the 95th percentile of exposure, adult females had BP-3
concentrations 3.5 times greater than those of adult males.
Mean concentrations also differed significantly among the different
racial/ethnic groups. Non-Hispanic whites were 6.8 times more likely
and Mexican Americans were 4 times more likely to have BP-3
concentrations above the 95th percentile compared with non-Hispanic
blacks. These differences likely result from increased use of
sunscreens by people with lighter skin pigmentation.
According to the authors, the NHANES 2003–2004 data can be used to
establish a nationally representative baseline assessment of exposure.
Moreover, the data could aid risk assessments for BP-3 exposure if
future toxicologic or epidemiologic studies suggest the need for such
research, and may encourage further research to determine the potential
public health impact of exposure at the levels reported.
originally published on http://www.ehponline.org
